Brigitte Hamann (née Deitert; 26 July 1940 – 4 October 2016) was a German-Austrian author and historian based in Vienna.
Born in Essen, Germany, Hamann studied history in Münster and Vienna and for a time worked as a journalist in her native Essen. In 1965 she married the historian and university professor Günther Hamann (1924–1994), moved to Vienna and obtained Austrian in addition to German citizenship. The couple have three children, one of them being the journalist and feminist Sibylle Hamann. She worked with her husband at the University of Vienna and in 1978 obtained her doctor's degree on the basis of a thesis on the life of Crown Prince Rudolf of Austria, which was published in book form that same year. She described her working method as follows: "(Coming from Germany) I had a different view of Austria, and I began to write with a certain detachment".
The success of this first book led to others, notably on Empress Elisabeth of Austria, Adolf Hitler, and Winifred Wagner.
Hamann's 1999 book, Hitler's Vienna: A Dictator's Apprenticeship, examined how societal attitudes at the time shaped Hitler's anti-Semitic views during his time in Vienna between 1908 and 1913, and the effects of his inordinate fear of both infection and women. Following the publication of The Hidden Hitler by the historian and University of Bremen professor Lothar Machtan, Hamann investigated claims about Hitler's homosexuality and appears in the 2004 HBO documentary film, Hidden Fuhrer: Debating the Enigma of Hitler's Sexuality, by the American documentarians Fenton Bailey and Randy Barbato.